This instrument lets you listen to the secret sounds of electronics

LOM's Elektrosluch might not be for everyone, but sometimes weird is wonderful.

You might not know it, but right now there's a weird and wonderful cacophony of sounds whizzing by your ears. Those sounds, generated by the electromagnetic fields of electronic devices like mobile phones, laptops, Wi-Fi routers, or even electric vehicles like cars, buses, and trains, can't be heard by our feeble human hearing. But what if you had a way to take those those sounds, and translate them into something we could hear? Maybe even something musical?

LOM, a Slovak record label that specialises in field recordings and odd sounds, has done just that with a range of hardware that captures the tonal weirdness of electromagnetic fields. The most interesting of the bunch is the Elektrosluch, a device now in its third revision, which combines an operational amplifier with two electromagnetic transducers and a gain pot (up to 50 dB). Like acoustic (sound) waves, electromagnetic fields have a certain frequency and wavelength. The 230V mains electricity in the UK, for example, runs at 50Hz. The transducers simply take those frequencies and translate them into acoustic frequencies our ears can understand.

Further Reading

While that process is nothing new (if you ever stick your mobile phone on top of a speaker, you'll recognise the effect) the Elektrosluch is unique in that it pairs those transducers with a small amplifier and audio outputs that make it easy to pipe the resultant sounds out to a recording device. Best of all, the Elektrosluch is small enough to carry around in a pocket, and is powered by just a single 9V battery. As LOM demonstrates in the audio clip below, you can take the Elektrosluch pretty much anywhere and capture sounds. They won't always be appealing, as the trolleybus clip shows, but being able to listen in to an otherwise silent world is fascinating.

Some music made with the Elektrosluch

The Elektrosluch 3+ can be had for €100 direct from LOM, while those who don't mind a little tinkering can pick up a kit version for €40. Both are open source too, with the schematics available on Github. LOM also sells the Elektrouši, a pair of electromagnetic microphones you can use with an existing portable recorder, and has plans to release the Elektrosluch Priezor, a hyper-sensitive instrument that will detect atmospheric sounds in VLF radio bands.